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This paper describes the thermo-elasto-plastic analysis of bath and spray quenched AISI
316L cylinders. A suitably detailed continuum deformation analysis approach presented here is
implemented within the framework of commercial Finite Element (FE) package ABAQUS. The results
of the numerical analysis are compared with the residual elastic strains measured experimentally using
neutron diffraction. The good agreement between measured and modelled residual elastic strains
provides a basis for careful analysis of the residual elastic strain development resulting from two
different quench methods. The conclusions drawn from the analysis provides a better understanding of
quench processsing, so that the effects of different heat removal efficiencies of such processing
technique can be taken advantage of to generate favourable residual elastic stress and deformation and
microstructural distributions with quench processed components.

Abstract: A method for the numerical estimation of the final hardness distribution of heat treated aluminum alloys was developed and implemented into a commercial finite element (FE) tool. Jominy end-quench tests were carried out in order to determine the quench sensitivity of the aluminum alloy EN AW-6082. The hardness distribution of the alloy after end-quenching was related to the corresponding cooling rates. The derived relation was tested for an industrial application by investigating the local heat treatment of a prototype crash absorbing structure. Numerical estimations were validated with experimental measurements. Effectiveness of the derived method and possible improvements were discussed.

Abstract: After the extrusion process most aluminium alloy profiles don´t satisfy the necessary strength requirements. An increase of strength can be obtained by age hardening of hardenable aluminium alloys. Age hardening includes the three steps of solution annealing, quenching and aging and is usually carried out in a separate process after extrusion. The integration of the sub-steps solution annealing and quenching in the extrusion process results in a marked reduction of the complete process chain. The applicability of this integration depends primarily on the quenching power of the cooling module and on the quench sensitivity of the aluminium alloy. Using the finite element method the non-steady-state process of quenching the profiles after leaving the extrusion press has been simulated. The boundary conditions for quenching are varied for a gas nozzle field and a spray cooling using heat transfer coefficients based on experiments. The simulation results support the design of gas nozzle fields or spray cooling for the extrusion process of different aluminium alloys.

Abstract: With the development of fracturing mechanics, there has been growing recognition that the research on the residual stress of heat treatment becomes attractive. Metal cylinder as the research object, through upbuilding the mathmatic model and sovling the heat conduction equation, whose test data are regarded as the boundary condition can be used to get the distributing temperature function of the workpiece. From this function, it can be deducted the quenching residual stress functions of the club-shaped metal that is resulted from heat stress during quenching. The elastic-plastic transition temperature and elastic modulus which are measuerd can be used to get the calculated value of residual stress by this formula.

Abstract: Heat transfer coefficient is one of the most important boundary conditions for quenching process simulation. It depends on many factors, such as material, size, surface conditions of a part, and so on. It is, therefore, difficult to evaluate the heat transfer coefficient accurately. T In the environment for large modules P20 and the actual heat transfer conditions, the off-line air-cooling heat transfer coefficient of C are simulated by using empirical equations.

Abstract: The thermal parameters of 3Cr2Mo plastic die steel were tested. The temperature fields of 3Cr2Mo plastic die steel with the thickness 120mm were calculated and analyzed under two quenching processes. The results showed that for interrupted process the cooling velocity was faster when the temperature was more than 500°C, which was not in the transformation zone of bainite and martensite. And the fast cooling rate effectively avoided the pearlite appearance. When the temperature was less than 500°C, the cooling velocity under interrupted cooing process was slower, which avoided the big microstructure stress. So for the 3Cr2Mo plastic die steel with the thickness 120mm, the interrupted process was better. In the paper, the hardness was tested after interrupted cooling process and tempering. The tempering hardness difference was less than or equal to 3HRC. The study provided references for large plastic die steel on-line pre-hardening process formulation and optimization.